DUBAI: The world’s tallest building disappeared behind a grey layer of dust on Wednesday as sandstorms that have swept the Middle East hit the United Arab Emirates, prompting weather and traffic warnings.

The 828-metre (2,716 ft, 6ins) Burj Khalifa, which towers over Dubai and is usually visible across the busy financial hub, retreated behind a curtain of airborne dirt that shrouded much of the country.

The UAE is just the latest country in the path of sandstorms that have smothered Iraq, Kuwait, Saudi Arabia, Iran and others in recent days, closing airports and schools and sending thousands to hospital with breathing problems.

Capital city Abu Dhabi’s air quality index (AQI) soared into the “hazardous” zone overnight, according to waqi.info and the Plume pollution app.

The Middle East’s sandstorms are becoming more frequent and intense, a trend associated with overgrazing and deforestation, overuse of river water and more dams.

Experts say the phenomenon could worsen as climate change warps regional weather patterns and drives desertification.

Emirati authorities issued a nationwide warning urging residents to remain vigilant.

“Abu Dhabi Police urges drivers to be cautious due to low visibility during high winds and dust,” the police force tweeted, as residents took to social media to publish photos and videos.